U.S. patent application number 15/309668 was filed with the patent office on 2017-05-18 for fluoropolymer compositions.
The applicant listed for this patent is RHODIA OPERATIONS, SOLVAY SPECIALTY POLYMERS ITALY S.P.A.. Invention is credited to Arnaud BOURDETTE, Fiorenza D'APRILE, Ivan FALCO, Alessio MARRANI.
Application Number | 20170137658 15/309668 |
Document ID | / |
Family ID | 50736021 |
Filed Date | 2017-05-18 |
United States Patent
Application |
20170137658 |
Kind Code |
A1 |
MARRANI; Alessio ; et
al. |
May 18, 2017 |
FLUOROPOLYMER COMPOSITIONS
Abstract
The present invention pertains to a fluoropolymer composition,
to a process for the manufacture of said fluoropolymer composition
and to uses of said fluoropolymer composition in various
applications, in particular to uses of fluoropolymer films
obtainable therefrom in electrical or electronic devices.
Inventors: |
MARRANI; Alessio; (Lecco,
IT) ; D'APRILE; Fiorenza; (Nova Milanese, IT)
; FALCO; Ivan; (Sedriano, IT) ; BOURDETTE;
Arnaud; (Chelles, FR) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
SOLVAY SPECIALTY POLYMERS ITALY S.P.A.
RHODIA OPERATIONS |
Bollate
Paris |
|
IT
FR |
|
|
Family ID: |
50736021 |
Appl. No.: |
15/309668 |
Filed: |
May 6, 2015 |
PCT Filed: |
May 6, 2015 |
PCT NO: |
PCT/EP2015/059924 |
371 Date: |
November 8, 2016 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
C08J 2327/16 20130101;
C08J 3/091 20130101; C09D 127/16 20130101; H01L 41/317 20130101;
H01L 41/193 20130101; H01L 41/45 20130101; C23C 16/56 20130101;
C08J 3/095 20130101 |
International
Class: |
C09D 127/16 20060101
C09D127/16; C23C 16/56 20060101 C23C016/56; H01L 41/317 20060101
H01L041/317; H01L 41/45 20060101 H01L041/45; C08J 3/09 20060101
C08J003/09; H01L 41/193 20060101 H01L041/193 |
Foreign Application Data
Date |
Code |
Application Number |
May 9, 2014 |
EP |
14305678.6 |
Claims
1. A composition [composition (C)] comprising: (A) at least one
fluoropolymer [polymer (F)] comprising: from 30% to 82% by moles,
with respect to the total amount by moles of recurring units of the
polymer (F), of recurring units derived from vinylidene fluoride
(VDF) and from 18% to 70% by moles, with respect to the total
amount by moles of recurring units of the polymer (F), of recurring
units derived from trifluoroethylene (TrFE) and, optionally, at
least one fluorinated monomer [monomer (F)] different from VDF and
TrFE, and (B) a liquid medium [medium (L)] comprising one or more
organic solvents selected from the group consisting of diesters of
formula (I.sub.de), esteramides of formula (I.sub.ea) and diamides
of formula (I.sub.da): R.sup.1O(O)C--Z.sub.de--C(O)OR.sup.2
(I.sub.de) R.sup.3O(O)C--Z.sub.ea--C(O)NR.sup.4R.sup.5 (I.sub.ea)
R.sup.5R.sup.4N(O)C--Z.sub.da--C(O)NR.sup.4R.sup.5 (I.sub.da)
wherein: R.sup.1 and R.sup.2, equal to or different from each
other, are independently selected from the group consisting of
C.sub.1-C.sub.3 hydrocarbon groups, R.sup.3 is selected from the
group consisting of C.sub.1-C.sub.20 hydrocarbon groups, and
R.sup.4 and R.sup.5, equal to or different from each other, are
independently selected from the group consisting of hydrogen and
C.sub.1-C.sub.36 hydrocarbon groups, optionally substituted, or
wherein R.sup.4 and R.sup.5, taken together, form a cyclic moiety
including the nitrogen atom to which they are bound, said cyclic
moiety being optionally substituted and/or optionally comprising
one or more heteroatoms, and mixtures thereof, and Z.sub.de,
Z.sub.ea and Z.sub.da, equal to or different from each other, are
independently linear or branched C.sub.2-C.sub.10 divalent alkylene
groups.
2. The composition (C) according to claim 1, wherein the medium (L)
is free from dimethylsulfoxide (DMSO).
3. The composition (C) according to claim 1, wherein the polymer
(F) comprises: from 45% to 81% by moles, with respect to the total
amount by moles of recurring units of the polymer (F), of recurring
units derived from vinylidene fluoride (VDF), from 19% to 55% by
moles, with respect to the total amount by moles of recurring units
of the polymer (F), of recurring units derived from
trifluoroethylene (TrFE) and optionally, from 0.01% to 15% by
moles, with respect to the total amount by moles of recurring units
of the polymer (F), of recurring units derived from at least one
hydrogenated monomer (H).
4. The composition (C) according to claim 1, wherein the polymer
(F) comprises: from 30% to 80% by moles, with respect to the total
amount by moles of recurring units of the polymer (F), of recurring
units derived from vinylidene fluoride (VDF), from 19% to 55% by
moles, with respect to the total amount by moles of recurring units
of the polymer (F), of recurring units derived from
trifluoroethylene (TrFE), from 1% to 15% by moles, with respect to
the total amount by moles of recurring units of the polymer (F), of
recurring units derived from at least one monomer (F) different
from VDF and TrFE and optionally, from 0.01% to 8% by moles, with
respect to the total amount by moles of recurring units of the
polymer (F), of recurring units derived from at least one
hydrogenated monomer (H).
5. The composition (C) according to claim 1, wherein the polymer
(F) comprises one or more chain branches comprising end groups of
formulae --CF.sub.2H and/or --CF.sub.2CH.sub.3.
6. The composition (C) according to claim 1, wherein the polymer
(F) comprises one or more chain branches comprising end groups of
formulae --CF.sub.2H and/or --CF.sub.2CH.sub.3 in an amount of at
least 30 mmoles/Kg per Kg of vinylidene fluoride (VDF) recurring
units.
7. The composition (C) according to claim 1, wherein the medium (L)
comprises a total amount of one or more organic solvents selected
from the group consisting of diesters of formula (I.sub.de),
esteramides of formula (I.sub.ea) and diamides of formula
(I.sub.da) of at least 50% by weight with respect to the total
weight of the medium (L).
8. The composition (C) according to claim 1, said composition (C)
comprising: (A) from 0.1% to 40% by weight of at least one polymer
(F) and (B) from 60% to 99.9% by weight of a medium (L).
9. The composition (C) according to claim 1, said composition (C)
further comprising one or more additives selected from the group
consisting of crosslinking agents and crosslinking initiators.
10. A process for the manufacture of the composition (C) according
to claim 1, said process comprising: heating a mixture comprising
at least one polymer (F) and a medium (L), under stirring, thereby
providing the composition (C).
11. The process according to claim 10, wherein the polymer (F) in
the mixture is used either in the form of particles or in the form
of pellets.
12. The process according to claim 10, wherein the mixture is
heated under stirring at a temperature of at least 20.degree.
C.
13. The process according to claim 10, wherein the mixture is
heated under stirring at a temperature of at most 80.degree. C.
14. A process for the manufacture of a fluoropolymer film [film
(F)], said process comprising: applying a composition (C) according
to claim 1 onto at least one surface of a substrate thereby
providing a wet film, and drying the wet film thereby providing the
fluoropolymer film [film (F)].
15. A process for the manufacture of an electrical or electronic
device, said process comprising: (i'') manufacturing a
fluoropolymer film [film (F)] according to the process of claim 14,
and (ii'') using the film (F) provided in step (i'') for
manufacturing said electrical or electronic device.
16. The process according to claim 14, wherein the wet film is
dried at a temperature comprised between 60.degree. C. and
200.degree. C.
Description
[0001] This application claims priority to European application No.
EP 14305678.6 filed on May 9, 2014, the whole content of this
application being incorporated herein by reference for all
purposes.
TECHNICAL FIELD
[0002] The present invention pertains to a fluoropolymer
composition, to a process for the manufacture of said fluoropolymer
composition and to uses of said fluoropolymer composition in
various applications.
BACKGROUND ART
[0003] Vinylidene fluoride (VDF) copolymers comprising recurring
units derived from trifluoroethylene (TrFE) have been used
extensively in the manufacture of electronic devices due to their
ease of processing, chemical inertness and attractive
ferroelectric, piezoelectric, pyroelectric and dielectric
properties.
[0004] As is well known, the term piezoelectric means the ability
of a material to exchange electrical for mechanical energy and vice
versa and the electromechanical response is believed to be
essentially associated with dimensional changes during deformation
or pressure oscillation. The piezoelectric effect is reversible in
that materials exhibiting the direct piezoelectric effect (the
production of electricity when stress is applied) also exhibit the
converse piezoelectric effect (the production of stress and/or
strain when an electric field is applied).
[0005] Ferroelectricity is the property of a material whereby this
latter exhibits a spontaneous electric polarization, the direction
of which can be switched between equivalent states by the
application of an external electric field.
[0006] Pyroelectricity is the ability of certain materials to
generate an electrical potential upon heating or cooling. Actually,
as a result of this change in temperature, positive and negative
charges move to opposite ends through migration (i.e. the material
becomes polarized) and hence an electrical potential is
established.
[0007] It is generally understood that piezo-, pyro-,
ferro-electricity in copolymers of VDF with TrFE is related to a
particular crystalline habit, so called beta-phase, wherein
hydrogen and fluorine atoms are arranged to give maximum dipole
moment per unit cell.
[0008] Copolymers comprising recurring units derived from
vinylidene fluoride (VDF) and trifluoroethylene (TrFE) are
typically provided as semi-crystalline copolymers which can be
shaped or formed into semi-crystalline, essentially unoriented and
unstretched, thermoplastic films or sheets or tubular-constructed
products via well-known processing methods such as extrusion,
injection moulding, compression moulding and solvent casting.
[0009] Nevertheless, more recently, developments of thin film
electronic devices and/or assemblies of layers of ferroelectric
polymers in three-dimensional arrays for increasing e.g. memory
density have called for different processing techniques, requiring
notably ability of the polymer to be patterned according to
lithographic techniques and/or for layers there from to be stacked
with annealing treatment on newly formed layer not affecting
previously deposited layers.
[0010] In these techniques, it remains nevertheless key to provide
for stable and homogeneous solutions of fluorinated polymers as
starting materials.
[0011] The vast majority of fluorinated polymers can be readily
dissolved in suitable solvents to form stable solutions. These
solvents include N-methylpyrrolidone (NMP), N,N-dimethylacetamide
(DMAC), N,N-dimethylformamide (DMF), dimethyl sulphoxide (DMSO) and
phthalates.
[0012] With regards to NMP, DMF and DMAC, which have been since
years the solvents of choice in the industry in solution-based
processes for the manufacture of thin film electronic devices,
these solvents are now facing environmental and safety concerns,
having regards to the safety risks associated to their handling and
to possible leakage/emissions in the environment, so questing for
substitution.
[0013] For instance, NMP has been notably classified according to
the European regulation (EC) No1272/2008 in the hazard class
Repr.1B code H360D (may damage the unborn child), Eye Irrit.2 code
H319, STOT SE 3 code H335, Skin Irrit.2 H315 and according to the
European directive 67/548/EEC it is classified as Reprotoxic Cat2
code R61, Xi codes R36/37/38. Further more it is submitted to the
Toxic Release Inventory (SARA Title III Section 313).
[0014] Similarly, DMAC is covered by index number 616-011-00-4 of
Regulation (EC) No 1272/2008 in Annex VI, part 3, Table 3.1 (the
list of harmonised classification and labelling of hazardous
substances) as toxic for reproduction category 1B (H360D: "May
damage the unborn child"). The corresponding classification in
Annex VI, part 3, Table 3.2 (the list of harmonised and
classification and labelling of hazardous substances from Annex Ito
Directive 67/548/EEC) of Regulation (EC) No 1272/2008 is toxic to
reproduction category 2 (R61: "May cause harm to the unborn
child").
[0015] Also, DMF has been classified as toxic to reproduction
category 1B (H360D: "May damage the unborn child") according to
Regulation (EC) No 1272/2008 and is included in Annex VI, part 3
(index number 616-001-00-X), Table 3.1 (list of harmonised
classification and labelling of hazardous substances). The
corresponding classification in Annex VI, part 3, Table 3.2 (the
list of harmonised classification and labelling of hazardous
substances from Annex I to Directive 67/548/EEC) of Regulation (EC)
No 1272/2008 is toxic to reproduction category 2 (R61: "May cause
harm to the unborn child.").
[0016] The present invention thus provides a solution for obviating
to environmental and safety concerns which arise in using NMP, DMF,
DMAC, phthalates or other similar solvents and provides an
alternative process for manufacturing fluoropolymer compositions
and films thereof.
SUMMARY OF INVENTION
[0017] It has been now found that by using the composition of the
present invention it is advantageously possible to solubilize
certain fluoropolymers at relatively low temperatures while
avoiding use of toxic organic solvents.
[0018] In a first instance, the present invention pertains to a
composition [composition (C)] comprising:
[0019] (A) at least one fluoropolymer [polymer (F)] comprising:
[0020] from 30% to 82% by moles, with respect to the total amount
by moles of recurring units of the polymer (F), of recurring units
derived from vinylidene fluoride (VDF) and [0021] from 18% to 70%
by moles, with respect to the total amount by moles of recurring
units of the polymer (F), of recurring units derived from
trifluoroethylene (TrFE) and, optionally, from at least one
fluorinated monomer [monomer (F)] different from VDF and TrFE,
and
[0022] (B) a liquid medium [medium (L)] comprising one or more
organic solvents selected from the group consisting of diesters of
formula (I.sub.de), esteramides of formula (I.sub.ea) and diamides
of formula (I.sub.da):
R.sup.1O(O)C--Z.sub.de--C(O)OR.sup.2 (I.sub.de)
R.sup.3O(O)C--Z.sub.ea--C(O)NR.sup.4R.sup.5 (I.sub.ea)
R.sup.5R.sup.4N(O)C--Z.sub.da--C(O)NR.sup.4R.sup.5 (I.sub.da)
[0023] wherein: [0024] R.sup.1 and R.sup.2, equal to or different
from each other, are independently selected from the group
consisting of C.sub.1-C.sub.3 hydrocarbon groups, [0025] R.sup.3 is
selected from the group consisting of C.sub.1-C.sub.20 hydrocarbon
groups, and [0026] R.sup.4 and R.sup.5, equal to or different from
each other, are independently selected from the group consisting of
hydrogen and C.sub.1-C.sub.36 hydrocarbon groups, optionally
substituted, being understood that R.sup.4 and R.sup.5 might be
part of a cyclic moiety including the nitrogen atom to which they
are bound, said cyclic moiety being optionally substituted and/or
optionally comprising one or more heteroatoms, and mixtures
thereof, and [0027] Z.sub.de, Z.sub.ea and Z.sub.da, equal to or
different from each other, are independently linear or branched
C.sub.2-C.sub.10 divalent alkylene groups.
[0028] For the purpose of the present invention, the term "liquid
medium [medium (L)]" is intended to denote a medium comprising one
or more compounds in liquid state at 20.degree. C. under
atmospheric pressure.
[0029] For the purpose of the present invention, the term "organic
solvent" is used in its usual meaning, that is to say that it
refers to an organic compound capable of dissolving another
compound (solute) to form a uniformly dispersed mixture at
molecular level. In the case the solute is a polymer such as the
polymer (F), it is common practice to refer to a solution of the
polymer in a solvent when the resulting mixture is clear and no
phase separation is visible in the system. Phase separation is
taken to be the point, often referred to as "cloud point", at which
the solution becomes turbid or cloudy due to formation of polymer
aggregates or at which the solution turns into a gel.
[0030] The term "gel" is used herein in its usual meaning, that is
to say that it refers to a substance which does not flow.
[0031] It has been found that the composition (C) of the invention
is advantageously a homogenous solution wherein at least one
polymer (F) is successfully dissolved in the medium (L) thereby
providing a clear solution with no phase separation.
[0032] In a second instance, the present invention pertains to a
process for the manufacture of the composition (C) of the
invention, said process comprising: [0033] (i) providing a mixture
comprising at least one polymer (F) and a medium (L), and [0034]
(ii) heating under stirring the mixture provided in step (i)
thereby providing the composition (C).
[0035] Under step (ii) of the process for the manufacture of the
composition (C), the mixture provided in step (i) is typically
heated under stirring at a temperature of at least 20.degree. C.,
preferably of at least 25.degree. C.
[0036] Under step (ii) of the process for the manufacture of the
composition (C), the mixture provided in step (i) is typically
heated under stirring at a temperature of at most 80.degree. C.,
preferably of at most 70.degree. C.
[0037] It has been found that the process of the invention may be
advantageously carried out at a temperature not higher than
70.degree. C., preferably not higher than 80.degree. C.
[0038] In a third instance, the present invention pertains to a
process for the manufacture of a fluoropolymer film [film (F)],
said process comprising: [0039] (i') providing a substrate, [0040]
(ii') providing a composition [composition (C)] as defined above,
[0041] (iii') applying the composition (C) provided in step (ii')
onto at least one surface of the substrate provided in step (i')
thereby providing a wet film, and [0042] (iv') drying the wet film
provided in step (iii') thereby providing the fluoropolymer film
[film (F)].
[0043] It has been found that the film (F) obtainable by the
process of the invention is advantageously a homogeneous
fluoropolymer film having good mechanical properties to be suitably
used in various applications.
[0044] For the purpose of the present invention, the term "film" is
intended to denote a flat piece of material having a thickness
smaller than either of its length or its width.
[0045] For the purpose of the present invention, the term
"substrate" is intended to denote either a porous or a non-porous
substrate.
[0046] By the term "porous substrate" it is hereby intended to
denote a substrate layer containing pores of finite dimensions. By
the term "non-porous substrate" it is hereby intended to denote a
dense substrate layer free from pores of finite dimensions.
[0047] Under step (iii') of the process for the manufacture of the
film (F), the composition (C) is applied onto at least one surface
of the substrate provided in step (i') typically by using a
processing technique selected from the group consisting of casting,
spray coating, roll coating, doctor blading, slot die coating,
gravure coating, ink jet printing, spin coating, screen printing,
brush, squeegee, foam applicator, curtain coating and vacuum
coating.
[0048] Under step (iv') of the process for the manufacture of the
film (F), the wet film provided in step (iii') is dried typically
at a temperature comprised between 60.degree. C. and 200.degree.
C., preferably at a temperature comprised between 70.degree. C. and
130.degree. C.
[0049] Drying can be performed either under atmospheric pressure or
under vacuum. Alternatively, drying can be performed under modified
atmosphere, e.g. under an inert gas, typically exempt notably from
moisture (water vapour content of less than 0.001% v/v).
[0050] The drying temperature will be selected so as to effect
removal by evaporation of one or more organic solvents from the
film (F) of the invention.
[0051] The present invention thus also pertains to the
fluoropolymer film [film (F)] obtainable by the process of the
invention.
[0052] The film (F) typically consists of a composition comprising
at least one polymer (F).
[0053] The film (F) is typically free from any organic solvent.
[0054] The composition (C) may further comprise one or more
additives.
[0055] The choice of the additives is not particularly limited
provided that they do not interfere with solubility of the
polymer(s) (F) in the medium (L).
[0056] Non-limitative examples of suitable additives include,
notably, pigments, UV absorbers, crosslinking agents, crosslinking
initiators, organic and inorganic fillers such as ceramics, glass,
silica, conductive metal particles, semiconductive oxides, carbon
nanotubes, graphenes, core-shell particles, encapsulated particles,
conductive salts, silicon-based particles.
[0057] Should the composition (C) further comprise one or more
additives, the film (F) thereby provided typically consists of a
composition comprising at least one polymer (F) and at least one
additive.
[0058] Should the composition (C) further comprise one or more
additives selected from the group consisting of crosslinking agents
and crosslinking initiators, the film (F) thereby provided is
advantageously a crosslinkable fluoropolymer film [film (FC)] which
typically consists of a composition comprising at least one polymer
(F) and at least one additive selected from the group consisting of
crosslinking agents and crosslinking initiators.
[0059] The crosslinking agent is typically a poly(meth)acrylic
compound [compound (PMA)] comprising end groups of formula:
--O--C(O)--C(R.sup.6).dbd.CR.sup.7R.sup.8
wherein each of R.sup.6, R.sup.7 and R.sup.8, equal to or different
from each other, is independently a hydrogen atom or a
C.sub.1-C.sub.3 hydrocarbon group.
[0060] The compound (PMA) is more preferably selected from the
group consisting of ethylene glycol di(meth)acrylate, diethylene
glycol di(meth)acrylate, triethylene glycol di(meth)acrylate,
tetraethylene glycol di(meth)acrylate, polyethylene glycol
di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, 1,3-butylene
glycol di(meth)acrylate, tripropylene glycol di(meth)acrylate,
ethoxylated bisphenol A di(meth)acrylate, cyclohexane dimethanol
di(meth)acrylate, tris[2-(acryloyloxy)ethyl]isocyanurate,
trimethylol propane triacrylate, ethylene oxide added trimethylol
propane triacrylate, pentaerythritol triacrylate,
tris(acrylooxyethyl)isocyanurate, dipentaerythritol hexaacrylate
and caprolactone denatured dipentaerythritol hexaacrylate.
[0061] The crosslinking initiator may be a photoinitiator
[initiator (PI)] or a thermal initiator [initiator (TI)].
[0062] The photoinitiator [initiator (PI)] is typically selected
from the group consisting of alpha-hydroxyketones,
phenylglyoxylates, benzyldimethyl ketals, alpha-aminoketones and
bis acyl phosphines.
[0063] Among alpha-hydroxyketones, mention can be made of
1-hydroxy-cyclohexyl-phenyl-ketone,
2-hydroxy-2-methyl-1-phenyl-1-propanone and
2-hydroxy-1-[4-(2-hydroxyethoxy)phenyl]-2-methyl-1-propanone.
[0064] Among phenylglyoxylates, mention can be made of
methylbenzoylformate, oxy-phenyl-acetic acid
2-[2-oxo-2-phenyl-acetoxy-ethoxy]-ethyl ester and oxy-phenyl-acetic
2-[2-hydroxy-ethoxy]-ethyl ester.
[0065] Among benzyldimethyl ketals, mention can be made of alpha,
alpha-dimethoxy-alpha-phenylacetophenone.
[0066] Among alpha-aminoketones, mention can be made of
2-benzyl-2-(dimethylamino)-1-[4-(4-morpholinyl) phenyl]-1-butanone
and
2-methyl-1-[4-(methylthio)phenyl]-2-(4-morpholinyl)-1-propanone.
[0067] Among bis acyl phosphines, mention can be made of
diphenyl-(2,4,6-trimethylbenzoyl)-phosphine oxide.
[0068] Among initiators (PI), those which are liquid at room
temperature are preferred.
[0069] A class of initiators (PI) which gave particularly good
results has been that of alpha-hydroxyketones, in particular
2-hydroxy-2-methyl-1-phenyl-1-propanone.
[0070] The amount of initiator (PI) in the composition (C) is not
particularly limited. It will be generally used in an amount
comprised between 0.01% and 10% by weight, with respect to the
total weight of the composition (C). According to an embodiment of
the invention, the composition (C) comprises at least one initiator
(PI) in an amount comprised between 3% and 7% by weight, with
respect to the total weight of the composition (C).
[0071] The thermal initiator [initiator (TI)] is typically selected
from the group consisting of organic peroxides.
[0072] The crosslinkable fluoropolymer film [film (FC)] is
crosslinked typically either by UV treatment under UV radiation or
by thermal treatment.
[0073] For the purpose of the present invention, the term "UV
radiation" is intended to denote electromagnetic radiation with a
wavelength shorter than that of visible light but longer than soft
X-rays. It can be subdivided into near UV (380-200 nm wavelength;
abbreviation: NUV), far or vacuum UV (200-10 nm; abbreviation: FUV
or VUV), and extreme UV (1-31 nm; abbreviation: EUV or XUV). NUV
having a wavelength of from 200 nm to 380 nm is preferred in the
process of the invention. Either monochromatic or polychromatic
radiation can be used.
[0074] UV radiation can be provided in the crosslinking process of
the invention by any suitable UV radiation source.
[0075] Thermal treatment is typically carried out at a temperature
comprised between 60.degree. C. and 150.degree. C., preferably
between 100.degree. C. and 135.degree. C.
[0076] The crosslinkable fluoropolymer film [film (FC)] may be a
patterned crosslinkable fluoropolymer film [film (FCp)].
[0077] For the purpose of the present invention, the term
"patterned crosslinkable fluoropolymer film [film (FCp)]" is
intended to denote a fluoropolymer film having whichever pattern
geometry.
[0078] In a fourth instance, the present invention pertains to use
of at least one fluoropolymer film [film (F)] in an electrical or
electronic device.
[0079] The present invention thus further pertains to a process for
the manufacture of an electrical or electronic device, said process
comprising: [0080] (i'') manufacturing a fluoropolymer film [film
(F)] according to the process of the invention, and [0081] (ii'')
using the film (F) provided in step (i'') for manufacturing said
electrical or electronic device.
[0082] Non-limitative examples of suitable electronic devices
include transducers, sensors, actuators, ferroelectric memories and
capacitors powdered by electrical devices.
[0083] The composition (C) advantageously comprises:
[0084] (A) from 0.1% to 40% by weight of at least one polymer (F)
and
[0085] (B) from 60% to 99.9% by weight of a medium (L).
[0086] The composition (C) typically comprises:
[0087] (A) from 0.2% to 30% by weight of at least one polymer (F)
and
[0088] (B) from 70% to 99.8% by weight of a medium (L).
[0089] For the purpose of the present invention, the term
"fluorinated monomer [monomer (F)]" is intended to denote an
ethylenically unsaturated monomer comprising at least one fluorine
atom.
[0090] Non-limitative examples of suitable monomers (F) notably
include the followings: [0091] (a) C.sub.2-C.sub.8 perfluoroolefins
such as tetrafluoroethylene (TFE) and hexafluoropropylene (HFP);
[0092] (b) perfluoroalkylethylenes of formula
CH.sub.2.dbd.CH--R.sub.f0, wherein R.sub.f0 is a C.sub.2-C.sub.6
perfluoroalkyl group; [0093] (c) chloro- and/or bromo- and/or
iodo-C.sub.2-C.sub.6 fluoroolefins such as chlorofluoroethylene
(CFE) and chlorotrifluoroethylene (CTFE); [0094] (d)
perfluoroalkylvinylethers of formula CF.sub.2.dbd.CFOR.sub.f1,
wherein R.sub.f1 is a C.sub.1-C.sub.6 perfluoroalkyl group, such as
perfluoromethylvinylether (PMVE) and perfluoropropylvinylether
(PPVE); [0095] (e) (per)fluorooxyalkylvinylethers of formula
CF.sub.2.dbd.CFOX.sub.0, wherein X.sub.0 is a C.sub.1-C.sub.12
oxyalkyl group or a C.sub.1-C.sub.12 (per)fluorooxyalkyl group
having one or more ether groups, e.g. perfluoro-2-propoxy-propyl
group; [0096] (f) (per)fluoroalkylvinylethers of formula
CF.sub.2.dbd.CFOCF.sub.2OR.sub.f2, wherein R.sub.f2 is a
C.sub.1-C.sub.6 (per)fluoroalkyl group, e.g. --CF.sub.3,
--C.sub.2F.sub.5, --C.sub.3F.sub.7, or a C.sub.1-C.sub.6
(per)fluorooxyalkyl group having one or more ether groups, e.g.
--C.sub.2F.sub.5--O--CF.sub.3; [0097] (g) functional
(per)fluorooxyalkylvinylethers of formula CF.sub.2.dbd.CFOY.sub.0,
wherein Y.sub.0 is selected from a C.sub.1-C.sub.12 alkyl group or
(per)fluoroalkyl group, a C.sub.1-C.sub.12 oxyalkyl group and a
C.sub.1-C.sub.12 (per)fluorooxyalkyl group having one or more ether
groups, Y.sub.0 comprising a carboxylic or sulfonic acid group, in
its acid, acid halide or salt form; [0098] (h) fluorodioxoles,
preferably perfluorodioxoles such as
2,2,4-trifluoro-5-trifluoromethoxy-1,3-dioxole.
[0099] Most preferred monomers (F) are chlorofluoroethylene (CFE),
chlorotrifluoroethylene (CTFE), perfluoromethylvinylether (PMVE),
tetrafluoroethylene (TFE) and hexafluoropropylene (HFP).
[0100] The polymer (F) may further comprise recurring units derived
from at least one hydrogenated monomer [monomer (H)].
[0101] For the purpose of the present invention, the term
"hydrogenated monomer [monomer (H)]" is hereby intended to denote
an ethylenically unsaturated monomer comprising at least one
hydrogen atom and free from fluorine atoms.
[0102] The monomer (H) is typically selected from the group
consisting of (meth)acrylic monomers of formula (II) and vinyl
ether monomers of formula (III):
##STR00001##
wherein each of RA, RB and Rc, equal to or different from each
other, is independently a hydrogen atom or a C.sub.1-C.sub.3
hydrocarbon group, Rx is a hydrogen atom or a C.sub.1-C.sub.5
hydrocarbon group comprising at least one hydroxyl group, and
R'.sub.x is a C.sub.1-C.sub.5 hydrocarbon group comprising at least
one hydroxyl group.
[0103] The polymer (F) may be amorphous or semi-crystalline.
[0104] The term "amorphous" is hereby intended to denote a polymer
(F) having a heat of fusion of less than 5 J/g, preferably of less
than 3 J/g, more preferably of less than 2 J/g, as measured
according to ASTM D-3418-08.
[0105] The term "semi-crystalline" is hereby intended to denote a
polymer (F) having a heat of fusion of from 10 J/g to 90 J/g,
preferably of from 30 J/g to 60 J/g, more preferably of from 35 J/g
to 55 J/g, as measured according to ASTM D3418-08.
[0106] The polymer (F) has typically a heat of fusion of from 10
J/g to 80 J/g, preferably of from 10 J/g to 60 J/g, more preferably
of from 10 J/g to 55 J/g, as measured according to ASTM D3418.
[0107] The polymer (F) has typically a melt flow index of at most
500 g/10 min, preferably of at most 200 g/10 min, more preferably
of at most 50 g/10 min, as measured according to ASTM D1238
(230.degree. C., 5 Kg).
[0108] The polymer (F) has typically a melt flow index of at least
0.1 g/10 min, preferably of at least 1 g/10 min, more preferably of
at least 1.5 g/10 min, as measured according to ASTM D1238
(230.degree. C., 5 Kg).
[0109] According to a first preferred embodiment of the invention,
the polymer (F) comprises: [0110] from 45% to 81% by moles, with
respect to the total amount by moles of recurring units of the
polymer (F), of recurring units derived from vinylidene fluoride
(VDF), [0111] from 19% to 55% by moles, with respect to the total
amount by moles of recurring units of the polymer (F), of recurring
units derived from trifluoroethylene (TrFE) and [0112] optionally,
from 0.01% to 15% by moles, with respect to the total amount by
moles of recurring units of the polymer (F), of recurring units
derived from at least one monomer (H).
[0113] According to a second preferred embodiment of the invention,
the polymer (F) comprises: [0114] from 30% to 80% by moles, with
respect to the total amount by moles of recurring units of the
polymer (F), of recurring units derived from vinylidene fluoride
(VDF), [0115] from 19% to 55% by moles, with respect to the total
amount by moles of recurring units of the polymer (F), of recurring
units derived from trifluoroethylene (TrFE), [0116] from 1% to 15%
by moles, with respect to the total amount by moles of recurring
units of the polymer (F), of recurring units derived from at least
one monomer (F) different from VDF and TrFE and [0117] optionally,
from 0.01% to 8% by moles, with respect to the total amount by
moles of recurring units of the polymer (F), of recurring units
derived from at least one monomer (H).
[0118] The polymer (F) can be manufactured either by aqueous
suspension polymerization or by aqueous emulsion
polymerization.
[0119] The polymer (F) is preferably manufactured by aqueous
emulsion polymerization of vinylidene fluoride (VDF),
trifluoroethylene (TrFE), optionally, at least one monomer (F)
different from VDF and TrFE and, optionally, at least one monomer
(H) in the presence of at least one radical initiator in a
polymerization medium comprising: [0120] water, [0121] at least one
surfactant and [0122] optionally, at least one non-functional
perfluoropolyether oil.
[0123] Polymerization pressure ranges typically between 10 bar and
45 bar, preferably between 15 bar and 40 bar, more preferably
between 20 bar and 35 bar.
[0124] The skilled in the art will choose the polymerization
temperature having regards, inter alia, of the radical initiator
used. Polymerization temperature is generally selected in the range
comprised between 80.degree. C. and 140.degree. C., preferably
between 95.degree. C. and 130.degree. C.
[0125] Emulsion polymerization process as detailed above have been
described in the art (see e.g. U.S. Pat. No. 4,990,283 (AUSIMONT
SPA (IT)) Feb. 5, 1991, U.S. Pat. No. 5,498,680 (AUSIMONT SPA) Mar.
12, 1996 and U.S. Pat. No. 6,103,843 (AUSIMONT SPA) Aug. 15,
2000).
[0126] Should the polymer (F) be manufactured by aqueous suspension
polymerization, the polymerization medium typically results in an
aqueous slurry comprising the polymer (F) from which said polymer
(F) is recovered by concentration and/or coagulation of said
aqueous slurry and then submitted to drying.
[0127] Should the polymer (F) be manufactured by aqueous emulsion
polymerization, the polymerization medium typically results in an
aqueous latex comprising the polymer (F) and at least one
surfactant from which said polymer (F) is recovered by
concentration and/or coagulation of said aqueous latex and then
submitted to drying.
[0128] Drying is typically carried out in suitable heating devices,
generally electric ovens or convection ovens. Drying is carried out
at a temperature typically up to 300.degree. C., preferably up to
200.degree. C., more preferably up to 100.degree. C. Drying is
carried out for a time typically of from 1 to 60 hours, preferably
of from 10 to 50 hours.
[0129] The polymer (F) is typically recovered by the polymerization
medium in the form of particles. The polymer (F) is commonly
recovered by the polymerization medium in the form of particles
such as flakes, rods, thread-like particles and mixtures
thereof.
[0130] The polymer (F) particles recovered by the polymerization
medium may be further processed by melt-processing techniques
thereby providing pellets.
[0131] Under step (i) of the process for the manufacture of the
composition (C), the polymer (F) may be used either in the form of
particles or in the form of pellets.
[0132] Under step (i) of the process for the manufacture of the
composition (C), the polymer (F) is preferably used in the form of
particles such as flakes, rods, thread-like particles and mixtures
thereof.
[0133] The particle size of the polymer (F) is not particularly
limited. The skilled in the art will select the proper particle
size of the polymer (F) in order to suitably adjust its time of
dissolution in the medium (L).
[0134] The polymer (F) is advantageously a linear polymer [polymer
(F.sub.L)] comprising linear sequences of recurring units derived
from vinylidene fluoride (VDF), trifluoroethylene (TrFE),
optionally, at least one monomer (F) different from VDF and TrFE
and, optionally, at least one monomer (H).
[0135] The polymer (F) is thus typically distinguishable from graft
polymers.
[0136] The polymer (F) is advantageously a random polymer [polymer
(F.sub.R)] comprising linear sequences of randomly distributed
recurring units derived from vinylidene fluoride (VDF),
trifluoroethylene (TrFE), optionally, at least one monomer (F)
different from VDF and TrFE and, optionally, at least one monomer
(H).
[0137] The polymer (F) is thus typically distinguishable from block
polymers.
[0138] The polymer (F) typically comprises one or more chain
branches comprising end groups of formulae --CF.sub.2H and/or
--CF.sub.2CH.sub.3, which usually originate from intra-chain
transfer (back-biting) during radical polymerization as shown in
the scheme here below:
##STR00002##
[0139] According to a first embodiment of the invention, the
polymer (F) comprises one or more chain branches comprising end
groups of formula --CF.sub.2H and/or --CF.sub.2CH.sub.3 in an
amount of less than 30 mmoles per Kg of vinylidene fluoride (VDF)
recurring units, preferably of less than 20 mmoles per Kg of VDF
recurring units [polymer (F-A)].
[0140] According to a second embodiment of the invention, the
polymer (F) comprises one or more chain branches comprising end
groups of formula --CF.sub.2H and/or --CF.sub.2CH.sub.3 in an
amount of at least 30 mmoles per Kg of vinylidene fluoride (VDF)
recurring units, preferably of at least 40 mmoles per Kg of VDF
recurring units [polymer (F-B)].
[0141] The polymer (F) is preferably a polymer (F-B) according to
this second embodiment of the invention.
[0142] It has been found that the polymer (F-B) may advantageously
dissolve faster in the medium (L).
[0143] Also, it has been found that the polymer (F-B) may
advantageously provide for a composition (C) advantageously
comprising dissolved therein up to 40% by weight of at least one
polymer (F-B) in the medium (L).
[0144] The medium (L) typically comprises a total amount of one or
more organic solvents selected from the group consisting of
diesters of formula (I.sub.de), esteramides of formula (I.sub.ea)
and diamides of formula (I.sub.da) as defined above of at least 50%
by weight, preferably at least 60% by weight, more preferably at
least 70% by weight, with respect to the total weight of the medium
(L).
[0145] In formula (I.sub.de), R.sup.1 and R.sup.2, equal to or
different from each other, are preferably independently selected
from the group consisting of C.sub.1-C.sub.3alkyl groups such as
methyl, ethyl and n-propyl groups, more preferably being methyl
groups.
[0146] In formula (I.sub.ea), R.sup.3 is preferably selected from
the group consisting of C.sub.1-C.sub.20 alkyl groups.
[0147] In formulae (I.sub.ea) and (I.sub.da), R.sup.4 and R.sup.5,
equal to or different from each other, are preferably independently
selected from the group consisting of C.sub.1-C.sub.20 alkyl,
C.sub.1-C.sub.20 aryl, C.sub.1-C.sub.20 alkyaryl and
C.sub.1-C.sub.20 arylalkyl groups, all said groups optionally
comprising one or more substituents, optionally comprising one or
more heteroatoms, and cyclic moieties comprising both R.sup.4 and
R.sup.5 and the nitrogen atom to which they are bound, said cyclic
moieties optionally comprising one or more heteroatoms such as
oxygen atoms or additional nitrogen atoms.
[0148] The expression "C.sub.1-C.sub.20 alkyl" is used according to
its usual meaning and it encompasses notably linear, cyclic,
branched saturated hydrocarbon groups having from 1 to 20 carbon
atoms, preferably from 1 or 2 to 10 carbon atoms, more preferably
from 1 to 3 carbon atoms.
[0149] The expression "C.sub.1-C.sub.20 aryl" is used according to
its usual meaning and it encompasses notably aromatic mono- or
poly-cyclic groups, preferably mono- or bi-cyclic groups,
comprising from 6 to 12 carbon atoms, preferably phenyl or naphthyl
groups.
[0150] The expression "C.sub.1-C.sub.20 arylalkyl" is used
according to its usual meaning and it encompasses linear, branched
or cyclic saturated hydrocarbon groups comprising, as substituent,
one or more aromatic mono- or poly-cyclic groups such as benzyl
groups.
[0151] The expression "C.sub.1-C.sub.20 alkylaryl" is used
according to its usual meaning and it encompasses aromatic mono- or
poly-cyclic groups comprising, as substituent, one or more alkyl
groups such as linear, cyclic, branched saturated hydrocarbon
chains having from 1 to 14 carbon atoms and preferably from 1 or 2
to 10 carbon atoms.
[0152] In formula (I.sub.ea), R.sup.3 is more preferably selected
from the group consisting of methyl, ethyl, hydroxyethyl, n-propyl,
isopropyl, n-butyl, isobutyl, terbutyl, n-pentyl, isopentyl,
n-hexyl and cyclohexyl groups, most preferably from the group
consisting of methyl, ethyl and hydroxyethyl groups.
[0153] According to a first embodiment of the invention, Z.sub.de
in formula (I.sub.de), Z.sub.ea in formula (I.sub.ea) and Z.sub.da
in formula (I.sub.da) are branched C.sub.2-C.sub.10 divalent
alkylene groups, preferably branched C.sub.3-C.sub.6 divalent
alkylene groups.
[0154] According to this first embodiment of the invention,
Z.sub.de in formula (I.sub.de), Z.sub.ea in formula (I.sub.ea) and
Z.sub.da in formula (I.sub.da) are preferably selected from the
group consisting of: [0155] Z.sub.MG groups of formula
--CH(CH.sub.3)--CH.sub.2--CH.sub.2-(MG.sub.a) or
--CH.sub.2--CH.sub.2--CH(CH.sub.3)-(MG.sub.b), [0156] Z.sub.ES
groups of formula --CH(C.sub.2H.sub.5)--CH.sub.2-(ES.sub.a) or
--CH.sub.2--CH(C.sub.2H.sub.5)-(ES.sub.b), and [0157] mixtures
thereof.
[0158] According to a first variant of this first embodiment of the
invention, the medium (L) comprises:
[0159] (a') at least one diester of formula (I'.sub.de), at least
one diester of formula (I''.sub.de) and, optionally, at least one
diester of formula (I'''.sub.de), or
[0160] (b') at least one esteramide of formula (I'.sub.ea), at
least one esteramide of formula (I''.sub.ea) and, optionally, at
least one esteramide of formula (I'''.sub.ea), or
[0161] (c') at least one esteramide of formula (I'.sub.ea), at
least one esteramide of formula (I''.sub.ea), at least one diamide
of formula (I'.sub.da), at least one diamide of formula
(I''.sub.da) and, optionally, at least one esteramide of formula
(I'''.sub.ea) and/or at least one diamide of formula (I'''.sub.da),
or
[0162] (d') combinations of (a') and/or (b') and/or (c'),
[0163] wherein:
is R.sup.1--O(O)C--Z.sub.MG--C(O)O--R.sup.2 (I'.sub.de)
is R.sup.3--O(O)C--Z.sub.MG--C(O)NR.sup.4R.sup.5 (I'.sub.ea)
is R.sup.5R.sup.4N(O)C--Z.sub.MG--C(O)NR.sup.4R.sup.5
(I'.sub.da)
is R.sup.1--O(O)C--Z.sub.ES--C(O)O--R.sup.2 (I''.sub.de)
is R.sup.3--O(O)C--Z.sub.ES--C(O)NR.sup.4R.sup.5 (I''.sub.ea)
is R.sup.5R.sup.4N(O)C--Z.sub.ES--C(O)NR.sup.4R.sup.5
(I''.sub.da)
is R.sup.1--O(O)C--(CH.sub.2).sub.4--C(O)O--R.sup.2 and
(I'''.sub.de)
is R.sup.3--O(O)C--(CH.sub.2).sub.4--C(O)NR.sup.4R.sup.5
(I'''.sub.ea)
is R.sup.5R.sup.4N(O)C--(CH.sub.2).sub.4--C(O)NR.sup.4R.sup.5
(I'''.sub.da)
wherein: [0164] Z.sub.MG is of formula
--CH(CH.sub.3)--CH.sub.2--CH.sub.2-(MG.sub.a) or
--CH.sub.2--CH.sub.2--CH(CH.sub.3)-(MG.sub.b), [0165] Z.sub.ES is
of formula --CH(C.sub.2H.sub.5)--CH.sub.2-(ES.sub.a) or
--CH.sub.2--CH(C.sub.2H.sub.5)-(ES.sub.b), [0166] R.sup.1 and
R.sup.2, equal to or different from each other, are independently
selected from the group consisting of C.sub.1-C.sub.3 alkyl groups,
[0167] R.sup.3 is selected from the group consisting of
C.sub.1-C.sub.20 alkyl, C.sub.1-C.sub.20 aryl, C.sub.1-C.sub.20
alkyaryl and C.sub.1-C.sub.20 arylalkyl groups, and [0168] R.sup.4
and R.sup.5, equal to or different from each other, are
independently selected from the group consisting of
C.sub.1-C.sub.20 alkyl, C.sub.1-C.sub.20 aryl, C.sub.1-C.sub.20
alkyaryl, arylalkyl groups, all said groups optionally comprising
one or more substituents, optionally having one or more
heteroatoms, and cyclic moieties comprising both R.sup.4 and
R.sup.5 and the nitrogen atom to which they are bound, said cyclic
moieties optionally comprising one or more heteroatoms such as
oxygen atoms or additional nitrogen atoms.
[0169] In above mentioned formulae (I'.sub.de), (I''.sub.de),
(I'.sub.ea), (I''.sub.ea), (I'.sub.da), (I''.sub.da), R.sup.1,
R.sup.2 and R.sup.3, equal to or different from each other, are
preferably methyl groups, and R.sup.4 and R.sup.5, equal to or
different from each other, are preferably selected from the group
consisting of methyl, ethyl and hydroxyethyl groups.
[0170] According to this first variant of the first embodiment of
the invention, the medium (L) may comprise:
[0171] (aa') a diester mixture consisting essentially of: [0172]
from 70% to 95% by weight of at least one diester of formula
(I'.sub.de), [0173] from 5% to 30% by weight of at least one
diester of formula (I''.sub.de) and [0174] from 0 to 10% by weight
of at least one diester of formula (I'''.sub.de), as defined above,
or
[0175] (bb') an esteramide mixture consisting essentially of:
[0176] from 70% to 95% by weight of at least one esteramide of
formula (I'.sub.ea), [0177] from 5% to 30% by weight of at least
one esteramide of formula (I''.sub.ea) and [0178] from 0 to 10% by
weight of at least one esteramide of formula (I'''.sub.ea), as
defined above, or
[0179] (cc') a diester/esteramide/diamide mixture consisting
essentially of: [0180] from 1.4% to 1.9% by weight of at least one
diester of formula (I'.sub.de), [0181] from 0.1% to 0.6% by weight
of at least one diester of formula (I''.sub.de), [0182] from 0 to
0.2% by weight of at least one diester of formula (I'''.sub.de),
[0183] from 70% to 95% by weight of at least one esteramide of
formula (I'.sub.ea), [0184] from 5% to 30% by weight of at least
one esteramide of formula (I''.sub.ea), [0185] from 0 to 10% by
weight of at least one esteramide of formula (I'''.sub.ea), [0186]
from 0.01% to 10% by weight of at least one diamide of formula
(I'.sub.da), [0187] from 0.01% to 5% by weight of at least one
diamide of formula (I''.sub.da) and [0188] from 0 to 1% by weight
of at least one diamide of formula (I'''.sub.da), or (dd') mixtures
of (aa') and/or (bb') and/or (cc'), as defined above.
[0189] Non-limitative examples of suitable media (L) wherein
Z.sub.de in formula (I.sub.de) and/or Z.sub.ea in formula
(I.sub.ea) and/or Z.sub.da in formula (I.sub.da) are branched
C.sub.2-C.sub.10 divalent alkylene groups, preferably branched
C.sub.3-C.sub.6 divalent alkylene groups, include, notably,
RHODIASOLV.RTM. IRIS solvents and RHODIASOLV.RTM. POLARCLEAN
solvents.
[0190] RHODIASOLV.RTM. IRIS solvent is a mixture consisting
essentially of at least 80% by weight of
H.sub.3CO(O)C--CH(CH.sub.3)--CH.sub.2--CH.sub.2--C(O)OCH.sub.3 and
H.sub.3CO(O)C--CH(C.sub.2H.sub.5)--CH.sub.2--C(O)OCH.sub.3.
[0191] RHODIASOLV.RTM. POLARCLEAN solvent is a mixture consisting
essentially of at least 80% by weight of
H.sub.3CO(O)C--CH(CH.sub.3)--CH.sub.2--CH.sub.2--C(O)N(CH.sub.3).sub.2
and
H.sub.3CO(O)C--CH(C.sub.2H.sub.5)--CH.sub.2--C(O)N(CH.sub.3).sub.2
[0192] According to a second embodiment of the invention, Z.sub.de
in formula (I.sub.de), Z.sub.ea in formula (I.sub.ea) and Z.sub.da
in formula (I.sub.da) are linear 02-010 divalent alkylene groups,
preferably linear C.sub.3-C.sub.6 divalent alkylene groups.
[0193] According to a variant of this second embodiment of the
invention, the medium (L) comprises:
[0194] (a'') at least one diester of formula (II.sup.4.sub.de), at
least one diester of formula (II.sup.3.sub.de) and at least one
diester of formula (II.sup.2.sub.de), or
[0195] (b'') at least one esteramide of formula (II.sup.4.sub.ea),
at least one esteramide of formula (II.sup.3.sub.ea) and at least
one esteramide of formula (II.sup.2.sub.ea), or
[0196] (c'') at least one esteramide of formula (II.sup.4.sub.ea),
at least one esteramide of formula (II.sup.3.sub.ea), at least one
esteramide of formula (II.sup.2.sub.ea), at least one diamide of
formula (II.sup.4.sub.da), at least one diamide of formula
(II.sup.3.sub.da) and at least one diamide of formula
(II.sup.2.sub.da), or
[0197] (d'') mixtures of (a'') and/or (b'') and/or (c''),
wherein:
is R.sup.1--OOC--(CH.sub.2).sub.4--COO--R.sup.2
(II.sup.4.sub.de)
is R.sup.1--OOC--(CH.sub.2).sub.3--COO--R.sup.2
(II.sup.3.sub.de)
is R.sup.1--OOC--(CH.sub.2).sub.2--COO--R.sup.2
(II.sup.2.sub.de)
is R.sup.3--OOC--(CH.sub.2).sub.4--C(O)NR.sup.4R.sup.5
(II.sup.4.sub.ea)
is R.sup.3--OOC--(CH.sub.2).sub.3--C(O)NR.sup.4R.sup.5
(II.sup.3.sub.ea)
is R.sup.3--OOC--(CH.sub.2).sub.2--C(O)NR.sup.4R.sup.5
(II.sup.2.sub.ea)
is R.sup.5R.sup.4N(O)C--(CH.sub.2).sub.4--C(O)NR.sup.4R.sup.5
(II.sup.4.sub.da)
is R.sup.5R.sup.4N(O)C--(CH.sub.2).sub.3--C(O)NR.sup.4R.sup.5
(II.sup.3.sub.da)
is R.sup.5R.sup.4N(O)C--(CH.sub.2).sub.2--C(O)NR.sup.4R.sup.5
(II.sup.2.sub.da)
[0198] wherein: [0199] R.sup.1 and R.sup.2, equal to or different
from each other, are independently selected from the group
consisting of C.sub.1-C.sub.3 alkyl groups, [0200] R.sup.3 is
selected from the group consisting of C.sub.1-C.sub.20 alkyl,
C.sub.1-C.sub.20 aryl, C.sub.1-C.sub.20 alkyaryl and
C.sub.1-C.sub.20 arylalkyl groups, and [0201] R.sup.4 and R.sup.5,
equal to or different from each other, are independently selected
from the group consisting of C.sub.1-C.sub.20 alkyl,
C.sub.1-C.sub.20 aryl, C.sub.1-C.sub.20 alkyaryl, arylalkyl groups,
all said groups optionally comprising one or more substituents,
optionally having one or more heteroatoms, and cyclic moieties
comprising both R.sup.4 and R.sup.5 and the nitrogen atom to which
they are bound, said cyclic moieties optionally comprising one or
more heteroatoms such as oxygen atoms or additional nitrogen
atoms.
[0202] In above mentioned formulae (II.sup.4.sub.de),
(II.sup.3.sub.de), (II.sup.2.sub.de), (II.sup.4.sub.ea),
(II.sup.3.sub.ea), (II.sup.2.sub.ea), (II.sup.4.sub.da),
(II.sup.3.sub.da), (II.sup.2.sub.da), R.sup.1, R.sup.2 and R.sup.3,
equal to or different from each other, are preferably methyl
groups, and R.sup.4 and R.sup.5, equal to or different from each
other, are preferably selected from the group consisting of methyl,
ethyl and hydroxyethyl groups.
[0203] According to certain preferred variants of this second
embodiment of the invention, the medium (L) may comprise:
[0204] (aa'') a diester mixture consisting essentially of
H.sub.3CO(O)C--(CH.sub.2).sub.4--C(O)OCH.sub.3,
H.sub.3CO(O)C--(CH.sub.2).sub.3--C(O)OCH.sub.3 and
H.sub.3CO(O)C--(CH.sub.2).sub.2--C(O)OCH.sub.3, or
[0205] (bb'') an esteramide mixture consisting essentially of
H.sub.3CO(O)C--(CH.sub.2).sub.4--C(O)N(CH.sub.3).sub.2,
H.sub.3CO(O)C--(CH.sub.2).sub.3--C(O)N(CH.sub.3).sub.2 and
H.sub.3CO(O)C--(CH.sub.2).sub.2--C(O)N(CH.sub.3).sub.2, or
[0206] (cc'') a diester mixture of consisting essentially of
H.sub.5C.sub.2O(O)C--(CH.sub.2).sub.4--C(O)OC.sub.2H.sub.5,
H.sub.5C.sub.2O(O)C--(CH.sub.2).sub.3--C(O)OC.sub.2H.sub.5 and
H.sub.5C.sub.2O(O)C--(CH.sub.2).sub.2--C(O)OC.sub.2H.sub.5, or
[0207] (dd'') an esteramide mixture consisting essentially of
H.sub.5C.sub.2O(O)C--(CH.sub.2).sub.4--C(O)N(CH.sub.3).sub.2,
H.sub.5C.sub.2O(O)C--(CH.sub.2).sub.3--C(O)N(CH.sub.3).sub.2 and
H.sub.5C.sub.2O(O)C--(CH.sub.2).sub.2--C(O)N(CH.sub.3).sub.2,
or
[0208] (ee'') an esteramide mixture consisting essentially of
H.sub.9C.sub.4O(O)C--(CH.sub.2).sub.4--C(O)N(CH.sub.3).sub.2,
H.sub.9C.sub.4O(O)C--(CH.sub.2).sub.3--C(O)N(CH.sub.3).sub.2 and
H.sub.9C.sub.4O(O)C--(CH.sub.2).sub.2--C(O)N(CH.sub.3).sub.2,
or
[0209] (ff'') mixtures thereof.
[0210] An exemplary embodiment of the variant listed above under
section (aa'') is a diester mixture consisting essentially of:
[0211] from 8% to 22% by weight of
H.sub.3CO(O)C--(CH.sub.2).sub.4--C(O)OCH.sub.3, [0212] from 57% to
67% by weight of H.sub.3CO(O)C--(CH.sub.2).sub.3--C(O)OCH.sub.3 and
[0213] from 18% to 28% by weight of
H.sub.3CO(O)C--(CH.sub.2).sub.2--C(O)OCH.sub.3.
[0214] Non-limitative examples of suitable diester-based mixtures
wherein Z.sub.de in formula (I.sub.de) and/or Z.sub.ea in formula
(I.sub.ea) and/or Z.sub.da in formula (I.sub.da) are linear
C.sub.2-C.sub.10 divalent alkylene groups, preferably linear
C.sub.3-C.sub.6 divalent alkylene groups, include, notably,
RHODIASOLV.RTM. RPDE solvents.
[0215] RHODIASOLV.RTM. RPDE solvent is a mixture consisting
essentially of at least 70% by weight of
H.sub.3CO(O)C--(CH.sub.2).sub.3--C(O)OCH.sub.3 and
H.sub.3CO(O)C--(CH.sub.2).sub.2--C(O)OCH.sub.3.
[0216] The medium (L) may further comprise at least one alkyl
acetate of formula (I.sub.aa):
R.sup.9--OC(O)CH.sub.3 (I.sub.aa)
[0217] wherein R.sup.9 is a linear, branched or cyclic
C.sub.3-C.sub.15 alkyl group, preferably a C.sub.6-C.sub.15 alkyl
group, more preferably a C.sub.6-C.sub.13 alkyl group, even more
preferably a C.sub.6-C.sub.12 alkyl group.
[0218] In formula (I.sub.aa), R.sup.9 is preferably selected from
the group consisting of cyclohexyl, n-hexyl, n-octyl, isooctyl,
n-decyl, isodecyl, undecyl and dodecyl groups.
[0219] The alkyl acetate of formula (I.sub.aa) as defined above is
preferably a cyclohexyl acetate.
[0220] Should the medium (L) further comprise at least one alkyl
acetate of formula (I.sub.aa) as defined above, the amount of the
alkyl acetate(s) of formula (I.sub.aa) in said medium (L) is
typically at most 50% by weight, preferably at most 40% by weight,
more preferably at most 30% by weight, with respect to the total
weight of the medium (L).
[0221] According to a third embodiment of the invention, the medium
(L) comprises:
[0222] (a''') at least one diester of formula (I.sub.de) and
[0223] (b''') at least one alkyl acetate of formula (I.sub.aa):
R.sup.9--OC(O)CH.sub.3 (I.sub.aa)
[0224] wherein R.sup.9 is a linear, branched or cyclic
C.sub.3-C.sub.15 alkyl group, preferably a C.sub.6-C.sub.15 alkyl
group, more preferably a C.sub.6-C.sub.13 alkyl group, even more
preferably a C.sub.6-C.sub.12 alkyl group.
[0225] According to a variant of this third embodiment of the
invention, the medium (L) comprises:
[0226] (aa''') a diester mixture consisting essentially of: [0227]
from 70% to 95% by weight of at least one diester of formula
(I'.sub.de), [0228] from 5% to 30% by weight of at least one
diester of formula (I''.sub.de) and [0229] from 0 to 10% by weight
of at least one diester of formula (I'''.sub.de), as defined above,
and
[0230] (bb''') at least one alkyl acetate of formula
(I.sub.aa):
R.sup.9--OC(O)CH.sub.3 (I.sub.aa)
[0231] wherein R.sup.9 is a linear, branched or cyclic
C.sub.3-C.sub.15 alkyl group, preferably a C.sub.6-C.sub.15 alkyl
group, more preferably a C.sub.6-C.sub.13 alkyl group, even more
preferably a C.sub.6-C.sub.12 alkyl group.
[0232] According to a preferred variant of this third embodiment of
the invention, the medium (L) comprises:
[0233] (aa''') from 50% to 80% by weight, preferably from 60% to
80% by weight of a diester mixture consisting essentially of:
[0234] from 70% to 95% by weight of at least one diester of formula
(I'.sub.de), [0235] from 5% to 30% by weight of at least one
diester of formula (I''.sub.de) and [0236] from 0 to 10% by weight
of at least one diester of formula (I'''.sub.de), as defined above,
and
[0237] (bb''') from 20% to 50% by weight, preferably from 20% to
40% by weight of at least one alkyl acetate of formula
(I.sub.aa):
R.sup.9--OC(O)CH.sub.3 (I.sub.aa)
[0238] wherein R.sup.9 is a linear, branched or cyclic
C.sub.3-C.sub.15 alkyl group, preferably a C.sub.6-C.sub.15 alkyl
group, more preferably a C.sub.6-C.sub.13 alkyl group, even more
preferably a C.sub.6-C.sub.12 alkyl group.
[0239] Diesters of formula (I.sub.de) which can be used in the
composition of the invention can be prepared notably according to
the teachings of EP 1991519 A (RHODIA OPERATIONS) Nov. 19, 2008.
Esteramides of formula (I.sub.ea), which can be used in the
composition of the invention optionally in combination with
diamides of formula (I.sub.da), can be prepared notably according
to the teachings of WO 2011/154661 (RHODIA OPERATIONS) Dec. 15,
2011 and WO 2009/092795 (RHODIA OPERATIONS) Jul. 30, 2009.
[0240] The medium (L) may further comprise dimethylsulfoxide (DMSO)
and, optionally, at least one further organic solvent different
from DMSO and from diesters of formula (I.sub.de), esteramides of
formula (I.sub.ea) and diamides of formula (I.sub.da) as defined
above.
[0241] The medium (L) is preferably free from DMSO.
[0242] Should the medium (L) comprise at least one further organic
solvent different from DMSO and from diesters of formula
(I.sub.de), esteramides of formula (I.sub.ea) and diamides of
formula (I.sub.da) as defined above, the amount of said organic
solvent(s) in said medium (L) is typically lower than 50% by
weight, preferably lower than 25% by weight, with respect to the
total weight of the medium (L).
[0243] Non limitative examples of suitable further organic solvents
include, notably, the followings: [0244] aliphatic hydrocarbons
including, more particularly, the paraffins such as, in particular,
pentane, hexane, heptane, octane, nonane, decane, undecane,
dodecane or cyclohexane, and naphthalene and aromatic hydrocarbons
and more particularly aromatic hydrocarbons such as, in particular,
benzene, toluene, xylenes, cumene, petroleum fractions composed of
a mixture of alkylbenzenes, [0245] aliphatic or aromatic
halogenated hydrocarbons including more particularly,
perchlorinated hydrocarbons such as, in particular,
tetrachloroethylene, hexachloroethane; partially chlorinated
hydrocarbons such as dichloromethane, chloroform,
1,2-dichloroethane, 1,1,1-trichloroethane,
1,1,2,2-tetrachloroethane, pentachloroethane, trichloroethylene,
1-chlorobutane, 1,2-dichlorobutane, monochlorobenzene,
1,2-dichlorobenzene, 1,3-dichlorobenzene, 1,4-dichlorobenzene,
1,2,4-trichlorobenzene or mixture of different chlorobenzenes,
[0246] aliphatic, cycloaliphatic or aromatic ether oxides, more
particularly, diethyl oxide, dipropyl oxide, diisopropyl oxide,
dibutyl oxide, methyltertiobutylether, dipentyl oxide, diisopentyl
oxide, ethylene glycol dimethyl ether, ethylene glycol diethyl
ether, ethylene glycol dibutyl ether benzyl oxide; dioxane,
tetrahydrofuran (THF), [0247] glycol ethers such as ethylene glycol
monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol
monopropyl ether, ethylene glycol monoisopropyl ether, ethylene
glycol monobutyl ether, ethylene glycol monophenyl ether, ethylene
glycol monobenzyl ether, diethylene glycol monomethyl ether,
diethylene glycol monoethyl ether, diethylene glycol mono-n-butyl
ether, [0248] glycol ether esters such as ethylene glycol methyl
ether acetate, ethylene glycol monoethyl ether acetate, ethylene
glycol monobutyl ether acetate, [0249] alcohols such as methyl
alcohol, ethyl alcohol, diacetone alcohol, [0250] ketones such as
acetone, methylethylketone, methylisobutyl ketone,
diisobutylketone, cyclohexanone, isophorone, [0251] linear or
cyclic esters such as methyl acetoacetate, dimethyl phthalate,
.gamma.-butyrolactone, [0252] linear or cyclic carboxamides such as
N,N-dimethylacetamide (DMAC), N,N-diethylacetamide,
dimethylformamide (DMF), diethylformamide or N-methyl-2-pyrrolidone
(NMP), [0253] organic carbonates for example dimethyl carbonate,
diethyl carbonate, dipropyl carbonate, dibutyl carbonate,
ethylmethyl carbonate, ethylene carbonate, vinylene carbonate,
[0254] phosphoric esters such as trimethyl phosphate, triethyl
phosphate, [0255] ureas such as tetramethylurea,
tetraethylurea.
[0256] For embodiments wherein the medium (L) comprises one or more
further organic solvents, the medium (L) is preferably free from
organic solvents qualified as Carcinogenic, Mutagenic or Toxic to
Reproduction according to chemical safety classification (CMR
solvents); more specifically, the medium (L) is advantageously
substantially free from NMP, DMF and DMAC.
[0257] The medium (L) is preferably free from any further organic
solvent.
[0258] Should the disclosure of any patents, patent applications,
and publications which are incorporated herein by reference
conflict with the description of the present application to the
extent that it may render a term unclear, the present description
shall take precedence.
[0259] The invention will be now described in more detail with
reference to the following examples whose purpose is merely
illustrative and not limitative of the scope of the invention.
[0260] Raw Materials
[0261] Polymer (F-1): VDF (56% by moles)-TrFE (44% by moles)
[0262] Polymer (F-2): VDF (75% by moles)-TrFE (25% by moles)
[0263] Polymer (F-3): VDF (80% by moles)-TrFE (20% by moles)
[0264] Polymer (F-4): VDF (94% by moles)-TrFE (6% by moles)
[0265] Polymer (F-5): VDF (89% by moles)-TrFE (11% by moles)
[0266] Polymer (F-6): VDF (83% by moles)-TrFE (17% by moles)
[0267] Polymer (F-7): VDF (63% by moles)-TrFE (28% by moles)-CTFE
(9% by moles)
[0268] Solvent (A): RHODIASOLV.RTM. IRIS solvent
[0269] Solvent (B): composition comprising 70% by weight of
RHODIALSOLV.RTM.
[0270] IRIS solvent and 30% by weight of cyclohexyl acetate.
[0271] Solvent (C): RHODIASOLV.RTM. RPDE solvent
[0272] Solvent (D): RHODIASOLV.RTM. POLARCLEAN solvent
[0273] Solvent (E): RHODIASOLV.RTM. DIB solvent consisting
essentially of
(H.sub.3C).sub.2HC--H.sub.2C--O(O)C--(CH.sub.2).sub.4--C(O)O--CH.sub.2--C-
H(CH.sub.3).sub.2,
(H.sub.3C).sub.2HC--H.sub.2C--O(O)C--(CH.sub.2).sub.3--C(O)O--CH.sub.2--C-
H(CH.sub.3).sub.2 and
(H.sub.3C).sub.2HC--H.sub.2C--O(O)C--(CH.sub.2).sub.2--C(O)O--CH.sub.2--C-
H(CH.sub.3).sub.2.
[0274] Solvent (F): 2,2-dimethyl-1,3-dioxolane-4-methanol
[0275] Manufacture of Polymer (F-1)
[0276] In an AISI 316 steel vertical autoclave equipped with a
stirrer working at 880 rpm, 1406 g of demineralized water was
introduced. The temperature was brought to 14.degree. C. 436 g of
vinylidene fluoride and 436 g of trifluoroethylene were fed
followed by 713 g of a Ca(OH).sub.2 solution having a concentration
of 40.25 DN/Kg, 26.5 g of a solution of BERMOCOLL.RTM. E 230 G
ethylhydroxyethyl cellulose with a concentration of 20 g/Kg, 3.11 g
of X16 and 8.3 g of diethylenecarbonate. The temperature was then
brought to 40.degree. C. until a pressure of 80 bar was reached.
The reaction was carried out until the pressure went down to 44
bar. The temperature was then brought to 55.degree. C. Once reached
29 bar, the temperature was brought to 60.degree. C.
[0277] When the pressure had reached 8 bar, the reactor was cooled
to room temperature and unloaded. The recovered polymer was washed
with demineralized water and dried at 100.degree. C. for 16
hours.
[0278] Characterization of the polymer (F-1):
[0279] Melt Flow Index: 1.68 g/10 minutes
[0280] Second melting temperature (T.sub.m2): 156.7.degree. C.
[0281] Curie temperature: 64.5.degree. C.
[0282] Crystallization temperature: 136.degree. C.
[0283] Manufacture of Polymer (F-2)
[0284] In an AISI 316 steel vertical autoclave equipped with
baffles and stirrer, working at 570 rpm, 3.5 litres of
demineralized water was introduced. The temperature was then
brought to reaction temperature of 120.degree. C. When this
temperature was reached, 32.5 g of a microemulsion prepared
according to Example 1 of U.S. Pat. No. 7,122,608 (SOLVAY SOLEXIS
S.P.A.) Oct. 17, 2006 and 7.35 bar of vinylidene fluoride were
introduced. A gaseous mixture of VDF and TrFE in a molar nominal
ratio of 75/25 was fed until reaching a pressure of 30 bar.
[0285] The composition of the gaseous mixture in the autoclave head
was analyzed by G.C. The gaseous phase was found to be formed of
the following compounds in the following molar percentages: 82.5%
VDF, 17.5% TrFE. 36 ml of di-tertbutyl peroxide (DTBP) was then fed
by means of a metering pump.
[0286] The polymerization pressure was maintained constant by
feeding the above mentioned monomeric mixture; when 2% of the
mixture had been fed, the temperature was lowered to 105.degree. C.
When 1150 g of the mixture had been fed, the reaction temperature
was kept constant and the pressure was let fall down up to 15 bar.
The reactor was then cooled to room temperature, the latex was
unloaded and coagulated by freezing for 48 hours. The polymer was
finally washed with demineralized water and dried at 100.degree.
C.
[0287] Characterization of the polymer (F-2):
[0288] Melt Flow Index: 5.9 g/10 minutes
[0289] Second melting temperature (T.sub.m2): 144.3.degree. C.
[0290] Curie temperature: 110.degree. C.
[0291] Crystallization temperature: 118.3.degree. C.
[0292] Manufacture of Polymer (F-3)
[0293] In an AISI 316 steel vertical autoclave equipped with a
stirrer working at 880 rpm, 1406 g of demineralized water was
introduced. The temperature was brought to 14.degree. C. 841 g of
vinilidene difluoride, 207 g of trifluoroethylene were fed followed
by 713 g of Ca(OH).sub.2 solution having a concentration of 40.25
DN/Kg, 26.5 g of a solution of BERMOCOLL.RTM. E 230 G
ethylhydroxyethyl cellulose with a concentration of 20 g/Kg, 3.11 g
of X16 and 8.3 g of diethylenecarbonate. The temperature was
brought to 40.degree. C. until a pressure of 80 bar was reached.
The reaction was carried out until the pressure went down to 46
bar. The temperature was then brought to 50.degree. C. Once reached
37.5 bars, the temperature was brought to 60.degree. C. When the
pressure had reached 7 bar, the reactor was cooled to room
temperature and unloaded. The recovered polymer was washed with
demineralized water and dried at 100.degree. C. for 16 hours.
[0294] Characterization of the polymer (F-3):
[0295] Melt Flow Index: 2.9 g/10 minutes
[0296] Second melting temperature (T.sub.m2): 149.7.degree. C.
[0297] Curie temperature: 117.77.degree. C.
[0298] Crystallization temperature: 128.degree. C.
[0299] Manufacture of polymer (F-4)
[0300] In an AISI 316 steel vertical autoclave equipped with
baffles and stirrer, working at 570 rpm, 3.5 litres of
demineralized water was introduced. The temperature was then
brought to reaction temperature of 120.degree. C. When this
temperature was reached, 32.5 g of a microemulsion prepared
according to Example 1 of U.S. Pat. No. 7,122,608 (SOLVAY SOLEXIS
S.P.A.) Oct. 17, 2006 and 11.5 bar of vinylidene fluoride were
introduced. A gaseous mixture of VDF and TrFE in a molar nominal
ratio of 94/6 was fed until reaching a pressure of 30 bar.
[0301] The composition of the gaseous mixture in the autoclave head
was analyzed by G.C. The gaseous phase was found to be formed of
the following compounds in the following molar percentages: 96.2%
VDF, 3.8% TrFE. 42 ml of di-tertbutyl peroxide (DTBP) was then fed
by means of a metering pump.
[0302] The polymerization pressure was maintained constant by
feeding the above mentioned monomeric mixture; when 2% of the
mixture had been fed, the temperature was lowered to 105.degree. C.
When 675 g of the mixture had been fed, the reaction temperature
was kept constant and the pressure was let fall down up to 15 bar.
The reactor was then cooled to room temperature, the latex was
unloaded and coagulated by freezing for 48 hours. The polymer was
finally washed with demineralized water and dried at 100.degree.
C.
[0303] Characterization of the polymer (F-4):
[0304] Melt Flow Index: 18.1 g/10 minutes
[0305] Second melting temperature (T.sub.m2): 140.52.degree. C.
[0306] Curie temperature: Not present
[0307] Crystallization temperature: 120.37.degree. C.
[0308] Manufacture of Polymer (F-5)
[0309] The same procedure for the manufacture of the polymer (F-3)
was followed but 918 g of vinylidene fluoride and 114 g of
trifluoroethylene were fed.
[0310] Characterization of the polymer (F-5):
[0311] Melt Flow Index: 8.2 g/10 minutes
[0312] Second melting temperature (T.sub.m2): 163.7.degree. C.
[0313] Curie temperature: 149.9.degree. C.
[0314] Crystallization temperature: 125.8.degree. C.
[0315] Manufacture of Polymer (F-6)
[0316] The same procedure for the manufacture of the polymer (F-2)
was followed but 9.2 bar of vinylidene fluoride was introduced and
a gaseous mixture of VDF and TrFE in a molar nominal ratio of 83/17
was fed until reaching a pressure of 30 bar.
[0317] The gaseous phase was found to be formed of the following
compounds in the following molar percentages: 85.7% VDF, 14.3%
TrFE.
[0318] Characterization of the polymer (F-6):
[0319] Melt Flow Index: 105 g/10 minutes
[0320] Second melting temperature (T.sub.m2): 138.12.degree. C.
[0321] Curie temperature: 129.8.degree. C.
[0322] Crystallization temperature: 123.6.degree. C.
[0323] Manufacture of Polymer (F-7)
[0324] In an AISI 316 steel vertical autoclave equipped with
baffles and stirrer, working at 570 rpm, 3.5 litres of
demineralized water was introduced. The temperature was then
brought to reaction temperature of 120.degree. C. When this
temperature was reached, 32.5 g of a microemulsion prepared
according to Example 1 of U.S. Pat. No. 7,122,608 (SOLVAY SOLEXIS
S.P.A.) Oct. 17, 2006, 5 bar of vinylidene fluoride and 0.5 bar of
chlorotrifluoroethylene were introduced. A gaseous mixture of VDF,
TrFE and CTFE in a molar nominal ratio of 63/28/9 was fed until
reaching a pressure of 30 bar.
[0325] The composition of the gaseous mixture in the autoclave head
was analyzed by G.C. The gaseous phase was found to be formed of
the following compounds in the following molar percentages: 81.6%
VDF, 11.9% TrFE and 6.5% CTFE. 20 ml of di-tertbutyl peroxide
(DTBP) was then fed by means of a metering pump.
[0326] The polymerization pressure was maintained constant by
feeding the above mentioned monomeric mixture; when 2% of the
mixture had been fed, the temperature was lowered to 105.degree. C.
When 587 g of the mixture had been fed, the reaction temperature
was kept constant and the pressure was let fall down up to 15 bar.
The reactor was then cooled to room temperature, the latex was
unloaded and coagulated by freezing for 48 hours. The polymer was
finally washed with demineralized water and dried at 80.degree. C.
for 48 hours.
[0327] Characterization of the polymer (F-7):
[0328] Melt Flow Index: 14.4 g/10 minutes
[0329] Second melting temperature: 118.6.degree. C.
[0330] Curie temperature: 20.9.degree. C.
[0331] Determination of Fluoropolymer Chain Ends
[0332] Fluoropolymer chain ends were determined according to the
method described in PIANCA, M., et al. End groups in
fluoropolymers. Journal of Fluorine Chemistry. 1999, vol. 95,
p.71-84. Concentration of relevant chain ends are expressed as
mmoles per kg of VDF recurring units.
[0333] Composition and properties of the fluoropolymers so obtained
are summarized in Table 1.
TABLE-US-00001 TABLE 1 TrFE VDF CTFE Total chain ends [% mol] [%
mol] [% mol] [mmol/kg of VDF] Polymer (F-1) 44% 56% -- 16 Polymer
(F-2) 25% 75% -- 92 Polymer (F-3) 20% 80% -- 15 Polymer (F-4) 6%
94% -- 76 Polymer (F-5) 11% 89% -- 13 Polymer (F-6) 17% 83% -- 144
Polymer (F-7) 28% 63% 9% 69
[0334] Determination of Solubility of the Fluoropolymer
Compositions
[0335] The solubility of a fluoropolymer in a solvent was measured
by using a Leica CLS 150 Led fiber optic light source microscope
Illuminator.
[0336] Data regarding dissolution properties of the fluoropolymer
compositions so obtained are summarized in Tables 2 to 4
hereinbelow.
[0337] A solution of a fluoropolymer in a solvent was obtained when
the resulting mixture was clear and no phase separation was visible
in the system as indicated by symbol "S" (soluble) in Table 2
hereinbelow.
[0338] A dispersion of a fluoropolymer in a liquid medium was
obtained when the resulting mixture was turbid or cloudy due to
formation of polymer aggregates as indicated by symbol "I"
(insoluble) in Tables 3 and 4 hereinbelow.
EXAMPLE 1
[0339] A fluoropolymer composition was manufactured by dissolving,
under stirring, either at 25.degree. C. or at 50.degree. C., any of
polymer (F-1), polymer (F-2), polymer (F-3) or polymer (F-7) in the
form of particles in solvent (A). The fluoropolymer composition was
kept stirred until complete dissolution of the polymer (F) in the
medium (L).
EXAMPLE 2
[0340] A fluoropolymer composition was manufactured by dissolving,
under stirring, either at 25.degree. C. or at 50.degree. C., any of
polymer (F-1), polymer (F-2), polymer (F-3) or polymer (F-7) in the
form of particles in solvent (B). The fluoropolymer composition was
kept stirred until complete dissolution of the polymer (F) in the
medium (L).
EXAMPLE 3
[0341] A fluoropolymer composition was manufactured by dissolving,
under stirring, either at 25.degree. C. or at 50.degree. C., any of
polymer (F-1), polymer (F-2), polymer (F-3) or polymer (F-7) in the
form of particles in solvent (C). The fluoropolymer composition was
kept stirred until complete dissolution of the polymer (F) in the
medium (L).
EXAMPLE 4
[0342] A fluoropolymer composition was manufactured by dissolving,
under stirring, either at 25.degree. C. or at 50.degree. C., any of
polymer (F-1), polymer (F-2), polymer (F-3) or polymer (F-7) in the
form of particles in solvent (D). The fluoropolymer composition was
kept stirred until complete dissolution of the polymer (F) in the
medium (L).
COMPARATIVE EXAMPLE 1
[0343] A fluoropolymer composition was manufactured by dispersing,
under stirring, either at 25.degree. C. or at 50.degree. C., any of
polymer (F-4), polymer (F-5) or polymer (F-6) in the form of
particles in solvent (A).
COMPARATIVE EXAMPLE 2
[0344] A fluoropolymer composition was manufactured by dispersing,
under stirring, either at 25.degree. C. or at 50.degree. C., any of
polymer (F-4), polymer (F-5) or polymer (F-6) in the form of
particles in solvent (B).
COMPARATIVE EXAMPLE 3
[0345] A fluoropolymer composition was manufactured by dispersing,
under stirring, either at 25.degree. C. or at 50.degree. C., any of
polymer (F-4), polymer (F-5) or polymer (F-6) in the form of
particles in solvent (C).
COMPARATIVE EXAMPLE 4
[0346] A fluoropolymer composition was manufactured by dispersing,
under stirring, either at 25.degree. C. or at 50.degree. C., any of
polymer (F-4), polymer (F-5) or polymer (F-6) in the form of
particles in solvent (D).
COMPARATIVE EXAMPLE 5
[0347] A fluoropolymer composition was manufactured by dispersing,
under stirring, either at 25.degree. C. or at 50.degree. C., any of
polymer (F-1), polymer (F-2), polymer (F-3), polymer (F-4), polymer
(F-5), polymer (F-6) or polymer (F-7) in the form of particles in a
liquid medium consisting of the solvent (E).
COMPARATIVE EXAMPLE 6
[0348] A fluoropolymer composition was manufactured by dispersing,
under stirring, either at 25.degree. C. or at 50.degree. C., any of
polymer (F-1), polymer (F-2), polymer (F-3), polymer (F-4), polymer
(F-5), polymer (F-6) or polymer (F-7) in the form of particles in a
liquid medium consisting of the solvent (F).
[0349] As shown in Table 2 hereinbelow, any of polymer (F-1),
polymer (F-2), polymer (F-3) or polymer (F-7) advantageously
dissolved in any of solvent (A), solvent (B), solvent (C) or
solvent (D) thereby providing clear solutions with no phase
separation up to 30% by weight, with respect to the total weight of
said solution, of said polymer (F-1), polymer (F-2), polymer (F-3)
or polymer (F-7).
[0350] In particular, polymer (F-2) and polymer (F-7) provided for
faster dissolution in any of solvent (A), solvent (B), solvent (C)
or solvent (D) thereby providing homogeneous solutions comprising
up to 30% by weight, with respect to the total weight of said
solution, of said polymer (F-2) or polymer (F-7).
TABLE-US-00002 TABLE 2 Ex. 1 Ex. 2 Ex. 3 Ex. 4 Solvent (A) Solvent
(B) Solvent (C) Solvent (D) 25.degree. C. 50.degree. C. 25.degree.
C. 50.degree. C. 25.degree. C. 50.degree. C. 25.degree. C.
50.degree. C. Polymer (F-1) 25% S 25% S 25% S 25% S 25% S 25% S 25%
S 25% S Polymer (F-2) 25% S 25% S 25% S 25% S 25% S 25% S 25% S 25%
S Polymer (F-3) 25% S 25% S 10% S 10% S 20% S 20% S 20% S 20% S
Polymer (F-7) 30% S 30% S 15% S 15% S 20% S 20% S 20% S 20% S
[0351] On the other hand, as shown in Table 3 hereinbelow, the
fluoropolymer compositions according to Comparative Examples 1 to 4
were turbid or cloudy due to formation of polymer aggregates even
at 5% by weight, with respect to the total weight of said
composition, of polymer (F-4), polymer (F-5) or polymer (F-6) in
any of solvent (A), solvent (B), solvent (C) or solvent (D).
TABLE-US-00003 TABLE 3 C. Ex. 1 C. Ex. 2 C. Ex. 3 C. Ex. 4 Solvent
(A) Solvent (B) Solvent (C) Solvent (D) 25.degree. C. 50.degree. C.
25.degree. C. 50.degree. C. 25.degree. C. 50.degree. C. 25.degree.
C. 50.degree. C. Polymer (F-4) 5% I 5% I 10% I 10% I 5% I 5% I 25%
I 25% I Polymer (F-5) 10% I 10% I 10% I 10% I 10% I 10% I 10% I 10%
I Polymer (F-6) 10% I 10% I 10% I 10% I 10% I 10% I 25% I 25% I
[0352] Also, as shown in Table 4 hereinbelow, the fluoropolymer
compositions according to Comparative Examples 5 and 6 were turbid
or cloudy due to formation of polymer aggregates even at 1% by
weight, with respect to the total weight of said composition, of
polymer (F-1), polymer (F-2), polymer (F-3), polymer (F-4), polymer
(F-5), polymer (F-6) or polymer (F-7) in any of solvent (E) or
solvent (F).
TABLE-US-00004 TABLE 4 C. Ex. 5 C. Ex. 6 Solvent (E) Solvent (F)
25.degree. C. 50.degree. C. 25.degree. C. 50.degree. C. Polymer
(F-1) 1% I 1% I 1% I 1% I Polymer (F-2) 1% I 1% I 1% I 1% I Polymer
(F-3) 1% I 1% I 1% I 1% I Polymer (F-4) 1% I 1% I 1% I 1% I Polymer
(F-5) 1% I 1% I 1% I 1% I Polymer (F-6) 1% I 1% I 1% I 1% I Polymer
(F-7) 1% I 1% I 1% I 1% I
[0353] The composition (C) according to the present invention may
be advantageously used in a process for the manufacture of
fluoropolymer films thereby providing for homogeneous fluoropolymer
films having good mechanical properties to be suitably used in
various applications including electrical or electronic
devices.
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